Microcline (var: Amazonite) (Carlsbad twin) (ex Brian Kosnar Collection)

Item Description

The famous Amazonite crystals from around the Pikes Peak area of Colorado are the finest examples of this blue-green variety of Microcline in the world. Most often, the crystals form in single blocky examples, but every once in a while you'll find an example with excellent twinning. The three main twinning laws for Microcline are Baveno, Manebach and Carlsbad, and in my experience, Carlsbad twins are the hardest to find from Colorado. This piece is a great example of these rarely seen twins featuring a pair of narrow prismatic crystals, showing textbook twinning for the Carlsbad twin law. The crystals have a soft blue-green color, best seen on the terminations, while the prism faces have a mixture of a grey-white hues with a light surface coating of another Feldspar species, presumably Albite. A small group of off-white bladed Cleavelandite sits as the base of the specimen for a nice touch. No repairs, the piece is undamaged and presents beautifully. A fine old piece dating back a few decades that would make a fine addition to any collection of Feldspars or minerals of Colorado. Valued between $1,500-$2,000. From the collection of Brian Kosnar.